Dependence of mechanical properties of trabecular bone on plate–rod microstructure determined by individual trabecula segmentation (ITS)

• Published in: Journal of biomechanics Vol. 47; no. 3; pp. 702 - 708
• Main Authors: Zhou, Bin, Sherry Liu, X, Wang, Ji, Lucas Lu, X, Fields, Aaron J, Edward Guo, X
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 07-02-2014; Elsevier Limited
• Subjects: Aged; Aged, 80 and over; Biomechanical Phenomena - physiology; Bone density; Bone Density - physiology; Compressive Strength - physiology; Elastic Modulus - physiology; Female; Femur Neck - diagnostic imaging; Femur Neck - physiology; Femur Neck - ultrastructure; Fractures, Bone - diagnostic imaging; Humans; Individual trabecula segmentation; Linear Models; Male; Mechancial properties; Mechanical properties; Microstructure; Middle Aged; Osteoporosis; Osteoporosis - physiopathology; Physical Medicine and Rehabilitation; Spine - diagnostic imaging; Spine - physiology; Spine - ultrastructure; Tibia - diagnostic imaging; Tibia - physiology; Tibia - ultrastructure; Trabecular bone; X-Ray Microtomography - methods; Trabecular bone; Mechancial properties; Individual trabecula segmentation; Microstructure
• ISSN: 0021-9290; 1873-2380
• DOI: 10.1016/j.jbiomech.2013.11.039

Abstract Individual trabecula segmentation (ITS) technique can decompose the trabecular bone network into individual trabecular plates and rods and is capable of quantifying the plate/rod-related microstructural characteristics of trabecular bone. This novel technique has been shown to be able to provide in-depth insights into micromechanics and failure mechanisms of human trabecular bone, as well as to distinguish the fracture status independent of area bone mineral density in clinical applications. However, the plate/rod microstructural parameters from ITS have never been correlated to experimentally determined mechanical properties of human trabecular bone. In this study, on-axis cylindrical trabecular bone samples from human proximal tibia ( n =22), vertebral body ( n =10), and proximal femur ( n =21) were harvested, prepared, scanned using micro computed-tomography (µCT), analyzed with ITS and mechanically tested. Regression analyses showed that the plate bone volume fraction (pBV/TV) and axial bone volume fraction (aBV/TV) calculated by ITS analysis correlated the best with elastic modulus ( R2 =0.96–0.97) and yield strength ( R2 =0.95–0.96). Trabecular plate-related microstructural parameters correlated highly with elastic modulus and yield strength, while most rod-related parameters were found inversely and only moderately correlated with the mechanical properties. In addition, ITS analysis also identified that trabecular bone at human femoral neck had the highest trabecular plate-related parameters while the other sites were similar with each other in terms of plate–rod microstructure.